Signal-transmitting apparatus



April 13, 1954 C. B. TRIMBLE SIGNAL-TRANSMITTING APPARATUS 2Sheets-Sheet 1 Original Filed March 15, 1946 INVENTOR.

CEBER/V B. Tfi/MBLE April 13, 1954 c. B. TRIMBLE SIGNAL-TRANSMITTINGAPPARATUS 2 Sheets-Sheet 2 Original Filed March 15, 1946 TIM/V5 FORMERINVENTOR- (f BERN B. Tfi/MBLE BY W Patented Apr. 13, 1954 UNITED STATESPATENT OFFICE 2,655,5 4,; 7 sIGivAL-Tn NsMrrTmG nrrana'rus cater Dayton,Ohio- Original application March 15,1946} Sei-iarNor 654,561, now'Patent No. 2,558,888, dated July 3, 1951"."Divided' and thisapplication March 17, 1951, Serial No. 216,228

3 Claims, (01. Mir-L351) This invention relatesifo a novel signaltrans.mittingappara'tus and. in particular to an ap-.

gparatus for generating and transmitting several kinds of signalsequences which can cause dif v ierent operations to be performed whenreceived lby a related receiving apparatus a This application is adivision of United States.

patentapplication SeriaLNo. 654,561, which was filed on. March 15,1946,and which issued on July 3, 1951,.as PatentNo. 2,558,883. I

-10 In the embodimentto illustrate the invention,

the novel transmitting apparatus forms a part of a remotecontrol systemin which the trans-.-

Initting apparatus can selectively send out different signal sequenceswhich can control a 'reneiving apparatus to cause the :operation of. al-

mechanism to be started and stopped at will and to cause the receivingapparatus to be reset to a starting condition at Will.

In the remote control system," the sending-app.-

paratusvis arranged to send. out a preassigned signal sequencecontaining a predeterminedw 'LlllllIlbBI of signals each consisting ofoscillations sat a, selected frequency, .F1, followed byafurther. a

number of signals each consisting of oscillations at a differentfrequency. F2, which may be fol--:

lowed by more signals at frequency F1 and then moretat frequency F2,etc., until-the desired sig- :nal sequence has been formed. i rElectronicflmeansare utilized to produce the located behind the 73(1)signals, and, merely by changing a few simple electrical connections,any desired combinations of signals which are made up of oscillations atfrequency F1 and signals which are made upZOfw' oscillations atfrequency F2 may be obtained. These conditions enable a wide variety insignal sequences to be obtained and also enable changes in the-signalsequences to be made readily.

The sending apparatus also is providedwith means which can cause adistinctive signalsequence to be sent to the receiving apparatus 12G,

causeathe receiving apparatus to be operated to restore various parts ofthe receiving-apparatus-we to homeor normal position before the sequenceof signalsis sent thereto, thus insuring that-the receiving apparatuswill always be set properly. before it begins to respond to the signalsequence and will-cause the operation of somenfurther means only if theproper signal sequence is received. I The special restoring signals mayihave of signals similar to those used in the signal 5Q. quence. a

apart.

ticular, characteristic ,which distinguishes, them,- fron tl e si nalsoigthfi, signal sequence, or they may copSiQhOidcertain preselectedcombination v v ztrequenciesused" in the sigma selected freque ciesiing' number of portions to various ones of invention wiifiia a mobilesending a aratus,

zriedby an automobile from v cla to control "a receivii'ig' a paratuscause the operation 'of seaweeds eases "'rhbtely to other desiredapparatus. 1

The sending appara-tusofthis emb'odiinentwill :ioe capable" ofgeneratingand respondingto a signal sequence usiri' consist ofoscillations at either f, hese f equencies. i

The sendin 'a paratus'is coupled t6 t emes. I

ing apparatus either by an electromagnetic field or by 'an-elec'trostatio field" nals "being'radiate' jfrdin antenna or loop ferent nurnber' e al a aplurali of 12 .16:

A further ob ot of the avenues;- is 'to provide generated a novel sendinmal eas nce can ive-o erated to generate 'special restoring signals w hcan operate" a receiyin'gj apparatus parts off the receiving apparatuspp lie initiate a further signal sequence to cause the operation 4 g ofmechani'smt'o' en thi s is done, the ic onsist qi acorrespondhiclfrespond selectively s earueuian adapted ier v v vorciosure operating nieclianis'm'fa'light and/or any I,twofrequenciesandcon twining"p-rese1ected*-niimbers of signals which e d ng uponthe a e cvt e s s-1 J lat he tremor the auto; mobile or at'some other convenient1ocatio;n thereon and being'received by an input means'or"antenna-mountedbn the garage, either inside e H sequence, containing a'predetermfried-combination of dif- 3 to be interrupted, if desired,before a complete operation thereof.

With these and incidental objects in View, the invention includescertain novel features of construction and combinations of parts, theessential elements of which are set forth in appended claims and apreferred form or embodiment of which is hereinafter described withreference to the drawings which accompany and form a part of thisspecification.

In said drawings:

Fig. 1 is a circuit diagram of the preferred form of the sendingapparatus.

Fig. 2 is a circuit diagram showing a modified form of sendingapparatus.

General description In order to explain the operation of the sendingapparatus, it will be described in connection with the remote control ofa garage door from a vehicle. The sending apparatus is adapted to beoperated from the storage battery of an automobile, and the form shownin Fig. 1 consists of an electron-coupled oscillator and a controllerwhich can control the oscillator to cause the oscillator to oscillateselectively at either of two selected frequencies to enable signals,made up of oscillations at either one or the other of these frequencies,to be generated.

The oscillator contains a vacuum tube which is provided with aninductance and capacitance in parallel in its grid circuit, the valuesof inductance and capacitance being so chosen that they will cause theoscillator to oscillate at a desired frequency F1 to enable signals madeup of oscillations at this frequency to be produced. When it is desiredto cause the oscillator to oscillate at a different frequency, F2, asecond capacitor, which provides an additional capacitance, is connectedacross the inductance and in parallel with the other capacitance andenables signals made up of oscillations at thi second frequency, F2, tobe generated.

The controller is a step-by-step operating switch which has one portionto control when the additional capacitance will be effective and thuscontrols the frequency at which the oscillator will operate, and hasanother portion to determine when the oscillator will operate.

At the end of an operation of the sending apparatus, the switch in thecontroller will be located in its normal or home position. When theswitch is given its first step of movement, it connects the secondcapacitor to a vibrator which is operable to connect the additionalcapacitance across the inductance and the other capacitance anddisconnect it therefrom at a high rate of speed. This causes theoscillator to produce signals made up of oscillations at F1 and signalsmade up of oscillations at F2 alternately in rapid succession. As longas the switch remains in the positiion which is one step out of homeposition, the rapidly alternating sig nals made up of oscillations at F1and F2 will be generated. In the embodiment used to explain theinvention, these signals will be distinctive from the signals of asignal sequence and will be effective to cause the receiving apparatusto operate and restore various parts thereof to their home or unoperatedcondition. This restoration of the parts of the receiving apparatuseliminates any error which might otherwise arise due to theunintentional operation of the receiving apparatus by stray signals orstatic, and insures that the receiving apparatus will respond properlyonly when the required signal sequence has been received.

After the switch has been in its first position long enough to allow theparts of the receiving apparatus to be restored, it can be given anotherstep of movement to its second position, where a third portion of theswitch takes over and causes the swtich to operate automatically step bystep forward until it resumes its home position. During this automaticoperation of the switch, its first-named portion controls the oscillatorto produce the signal sequence containing predetermined numbers ofsignals, each of which signals will contain oscillations at one or theother of the different selected frequencies.

In the instant embodiment, the normal signal sequence for causing anoperation of the dooroperating mechanism will consist of three signals,

each of which is made up of oscillations at F1, followed by foursignals, each of which is made up of oscillations at F2, then by twosignals at F1, six signals at F2, and finally three signals at F1. Whenit is dark and the lights of the automobile are lighted, mean in thelight circuit of the automobile will modify the control by the firstandsecond-named portions of the switch to cause an additional signal at F2to be transmitted following the normal signal sequence, which additionalsignal will be effective to control the light circuit in the garage tocause the lights in the garage to be lighted or extinguished asrequired.

If, after an operation of the door-operating mechanism has beeninitiated, it is desired to stop the operation of this mechanism, thestep-.- ping of the switch to its first position out of normal, orrestoring position, will, as an incident to the restoring of the partsof the receiving apparatus, cause the operation of the mechanism to beinterrupted immediately.

The sending apparatus and the receiving apparatus are coupled by eitheran electromagnetic field or an electrostatic field which radiates from acoil or antenna located at the front of the automobile each time asignal is generated.

The sending apparatus can readily be changed to utilize differentfrequencies merely by changing either the inductance or the capacitancevalues, or both, in the grid circuit of the oscillator. Similarly, thesignal sequence can readily be changed merely by changing a few circuitconnections in the switch of the controller in the sending apparatus, sothat the additional capacitance can be made effetcive in a differentdesired sequence.

Detailed description The circuit diagram of one form which the novelsending apparatus may take is shown in Fig. l, in which the usualstorage battery of the automobile is shown at 10. The positive terminalof the battery It] is connected to a normally open, manually operableswitch H, which, when operated to prepare the sending apparatus foroperation, connects the positive battery terminal over conductor I2 toone side of a cathode heating element of a vacuum tube l3 of theoscillator and also connects the positive battery terminal to a vibratorpower supply I4, which supplies potential to the anode of the tube l3.v

The negative terminal of the battery I0 is connected to ground, and thecircuits to the heating element and vibrator power supply, as .well asto the various other elements of the sending apparatus, are completed byalso connecting these quency F1 and will generate signals made up ofoscillations at F1.

Accordingly, as the wiper traverses contacts in positions from 2 through36, it will cause the required normal signal sequence to be generated.

When the lights of the automobile are lighted and the relay 3!! (Fig. 1)is energized, it will connect the capacitor 23 to the contact inpositionv 38 so that, when the wiper moves into engagement with thiscontact, it will connect this contact to a grounded contact and willcause the additional signal, made up of oscillations at F2 in themodified signal sequence, to be gen erated.

The portion (IS-3 of the switch controls the stepping of the switch. Asseen from Fig. 1, the manually-operable switch II, when operated,'alsoconnects positive terminal of the battery I 0, over conductor 46, to oneside of the switch-operating magnet CSM. The other side of theswitch-operating magnet CSM is connected over a self-interrupter contact6! to a conductor 48, which is connected directly to contacts inpositions 2 to 49 clockwise from home position in portion CS-3, as seenin Fig. 1. Conductor 43, which is connected to the home position contactin portion CS-3, over a normally open, manually-operable Stop andRestore switch 49, is also connected to the contact in the firstposition clockwise (Fig. 1) from home position in portion CS-3 over anormally open manually-operable Operate switch Whenever the circuit fromthe switch-operating magnet CSM is connected to a contact in the portionCS-3, it will be completed by the engagement of the wiper with thatcontact, because the wiper related to this bank of contacts is connectedto ground.

Accordingly, after switch H has been operated to prepare the sendingapparatus for operation, the operation of the Stop and Restore switch 49will complete the circuit through the wiper in its home position andwill cause the operating magnet CSM to be operated and move the wipersclockwise (Fig. 1), in all three portions, one step into their firstposition, where the wiper in the second portion CS-Z grounds thegrid-leak resistor I8 to render the oscillator operable, and the wiperin the first portion CS-l connects the additional capacitor to groundthrough the vibrator blade 35 to control the oscillator to cause signalsmade up of oscillations at F1 and signals made up of oscillations at F;to be generated alternately in rapid succession, which signals causevarious parts of the receiving apparatus to be restored to normal orhome position and any uncompleted operation of the garage door operatingmechanism to be interrupted.

When the wiper in portion CS-3 moves clockwise (Fig. 1) into its firstposition, it will open the circuit of the operating magnet CSM. Afterthe sending apparatus has operated to send out signals which are made upof oscillations at F1 and signals which are made up of oscillations atF2, alternately in rapid succession, for a sufiicient time to allow theparts of the receiving apparatus to be restored, the Operate switch 5!can be closed momentarily to complete the circuit to the operatingmagnet CSM to cause the wipers to be moved clockwise (Fig. 1) to theirsecond position. Since contacts in positions 2 to 49 inclusive in thethird portion (ZS-3 are connected to conductor 48, they will cause theoperating magnet CSM to be operated re- 8 peatedly as the wiper isstepped thereover and will cause the switch to self-operate into itshome position. This self-operation of the switch occurs at about fiftysteps per second, and, during this portion of the operation of theswitch, the required signal sequence is sent out.

The operation of the above-described portion of the novel remote controlsystem is as follows:

When the automobile is in the vicinity of or is approaching the garage,the sending apparatus, which is carried by the automobile, can be madeready for operation by closing the man-- ually operable switch H, whichconnects various parts of the sending apparatus to the positive terminalof the battery In of the automobile. Thereafter the Stop and Restoreswitch 49 can be operated to step the controller switch one step tocause signals at F1 and signals at F2 to be radiated alternately inrapid succession from the coil 21 when the frequencies F1 and F2 are inlower frequencies or from an antenna when the frequencies F1 and F2 arein the higher frequencies, which coil or antenna is conveniently locatedbehind the usual radiator grill or at some other convenient part at thefront of the automobile. The rapidly-alternating signals, which are madeup of oscillations at F1 and F2, operate the receiving apparatus torestore the several parts thereof to home position. When suflicient timehas elapsed to enable the parts of the receiving apparatus to have beenrestored, the switch 49 can be opened and the Operate switch 5!! can beoperated to complete the circuit to the switch-operating magnet CSM,which will be energized and step the controller switch into its secondposition, where the portion 05-3 of the switch will take over and causethe switch to be stepped forward automatically to home position, duringwhich stepping, portions CS-l and (IS-2 of the controller switch controlthe oscillator to generate the required signal sequence containing thepreselected numbers of signals, which are made up of oscillations atfrequencies F1 or F2.

It is obvious that the signal sequence could easily consist of signalsmade up of oscillations at any one of three or more selected frequenciesmerely by providing further additional capacitors, as 23, which could beconnected to desired ones of the contacts of th portion CSI to beconnected in parallel with the coil 2| and the capacitor 22, as in thecase of the additional capacitor 23, to cause the oscillator to generatethe additional selected frequencies.

The signal sequence also can readily b altered simply by changing theconnections between the capacitor 23 and the contacts in the portionCS-l and by making similar changes in the connections in the portionCS-Z.

Fig. 2 shows a modified form of sending apparatus which uses the shockexcitation of a resonant circuit to produce the desired signals and.which can be controlled to produce oscillations at different frequenciesas F1 and F2.

The signal generator includes a resonant circuit made up of aninductance coil 2la and capacitor 2211, which circuit is tuned tooscillate and generate signals which are made up of oscillations atfrequency F1, and also includes a second capacitor 23a, which can beconnected across the coil Zla and the capacitor 22a to change theresonance of the circuit and cause the circuit to oscillate at frequencyF2 to produce signals which Zarecmadei up otzzoscillations ate In ordertocause ith zresonant circuit to: oscillate, it :isgexcited by:armagnetic :field: set: up insa coil I wawhiehgfieldz influences thecoil :2 I a.

Coils IBILis connected :in series withr a capacitor I 8i-.-across is,sparkgape-I 82:; The lspark gap I82 is:connected-:across thehigh-ivoltageicoi-k I83 of a transtorm.ermivhieh is :zcapableonsupplyings ialternatingoperatingpotential to this-circuit; Radiofrequency-- chokeicoils I84. and 1 I85 are provided n; .to protectthercoii: I 831 When; the voltage builds 1; a. up :in :the coil I 83, it".Will; chargerthe capacitor I 81and;lwhen,theogap:llizmreakszdownncapacitor cl 8 Ii;will...-alsobe;.discharged etherethroughzand wit-hxcoilrl 80.: .will constitute :a:resonantzzcircuit u-havingra: lowzdecrement.

, c.Aslthecurrentifiows initheiicoilelSilmazfieldwill 1e berset up:whichrshock-excites the a,coil..'2:la and an causescthersignaiz-generatingicircuit toiosci-llate toeproduceoa esignahlmadeup ormscillations at E1 on. Entdependingcuporr whether iorznotzcapact "c-tore!iazisiinethecircuit.

- The; lenalsreenerated this zsignalegeneratlmingrcircuitr wilLberradiatedwirom wcom-12kt dienreetly ii-nthertrequencies are in :the;lower. orange lr.ifll010. trai'glrtgwire,iantenna..z;conneoted tooanoiniwz 8e, the giizequencies are inuthe :higher in lk'illfiber-circuit to the lowevoltageco-il; I86 eithetransformer will beprepared when the preparingcswitoh Ita is' closedto -connectone side ofthe coiltot-thegpositive,terminal ofnbattery Ina. Negative terminal ofbattery Ina is grounded, andthecircuit to coil I86fwil1be completed from1;; ,the ';other 'side" of the' coil, over normally, closed ppntaclr'I81 and contacts in portion (IS-2a. when ,the:groundedwiper inthisportion is moved ,into

- engagement therewith.

When the circuit to coil I86 is completed and current flows through thecoil, the resulting magnetic field will cause contact I81 to be openedto interrupt the current flow, causing the field to decay and allowingthe contact I81 to reclose. This building up and decay of the fieldresulting from the intermittent interruption of current in coil I86 byswitch I81 will induce the alternating potential in the high-voltagecoil I83, which causes the gap I82, to break down, and enables coil I88to cause the signal-generating circuit to oscillate and produce therequired signal.

The wiper in portion (IS-2a oi the controller switch will groundcontacts in positions 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 22, 24, 26, 28,30, 32, 34, and 36 clockwise from the normal or home position, shown inFig. 3, and will cause the signalgenerating means to oscillate wheneverthe wiper is on any one of these contacts.

The wiper in portion CS-Iw grounds capacitor 23a through the vibratorblade 35a in the first position clockwise from normal to cause signalsmade up of oscillations at frequency F1 and signals made up ofoscillations at frequency F2 to be generated alternately in rapidsuccession and grounds the capacitor directly in positions 8, 10, 12,14, 20, 22, 24, 26, 28, and steps clockwise from home position to causesignals made up of oscillations at frequency F2 to be generated wheneverthe wiper is in any one of these positions.

The wiper in portion CS-3a, in conjunction with switches 49a and 58a,controls the operation magnet CSMa to cause the stepping of the switchthrough its cycle of operation in the same manner as the wiper CS-3, andswitches 49 and 50 control the magnet CSM to cause stepping of i 5110theaswitchiduringthes' sending operation; as explainedinrconnectionwithtFig. 1.

a relay. 30a, which -.enables wipers in :portions GmCS-Iaeand CS-Zato-ground capacitor flw-and. r *coilaiI Bar-respectively; the:thirty-eighthposi- ",JitiOIFOfE'thGZSV/itChitU causetheextra-:signahmade up of oscillations at frequency F2, to be sentout to icontrol :the garage :light circuit.

is r iiflhe type -.of sending. apparatus shown in Fig. 2, 1 ;;therefore,:can. generate signals which will cause the operation of Y thedoor-operating mechanism 1 to be: interrupted and; thereceiving-apparatus to be; restored to::normal orhome positiom canlira-generate the normal signal sequence to cause an operation otthegarage-.door-operating mecha- 14213115111, and .can generate themodified signal sequence to cause an operation of thegarage-dooroperating; mechanism and to control: the oper- 20. ation ofthe garage lig-ht'circuit.

a W-hile the form of..theinvention shown and described hereinisgadmirablyiv adapted toslfulfill-the objects primarilmistated, .it .isto be": understood :that-it is not intended to confinertheinvenrion to:15 'the one form or emb-odiment disclosednherein for the-novelremotezcontrolrsystem issusceptible of owembodiment in various formsallicomingzwithin the scope of the claims WhiChTOllOzW.

30 i. In aetransmittingsystem-the combination of a. sendingapparatusrincluding :oscillating means ,,.,for,producin oscillationsselectively at either of "two .preselected frequencies, :fromwhiclroscillaytions atone of said frequencies;one-typecf signaliscOnStituted, andtfrom which'oscillations ata'the other of saidfrequencies nanother ,ty-pe ct-signal is constitutedflalfirstoscillatingYmeans control circuit having a time constant for controlling theoscillating means to cause it to oscillate at one 40 of said frequenciesto produce signals of said one type, a second oscillating means controlcircuit for modifying the time constants of said first circuit to causethe oscillating means to oscillate at the other of said frequencies toproduce signals of said other type, a signal sequence controlling switchhaving a plurality of banks of contacts and wipers moved past thecontacts of the banks in unison to complete circuits thereto, said firstcontrol circuit being connected to predetermined contacts of one of saidbanks to cause said oscillator to operate whenever a wiper is on one ofsaid predetermined contacts, and said second control circuit beingconnected to selected contacts of the other bank of contacts to causethe control of the oscillator to be modified whenever a wiper is on oneof said selected contacts to which the second control circuit isconnected, the

signal sequence controlling switch causing signals of said one type tobe generated when the wipers engage contacts to which only said firstcircuit 6 is connected and causing signals of the other of said types tobe generated when the wipers simultaneously engage contacts in bothbanks which are connected to the first and second control circuits, theparticular connections to the contacts controlling the oscillating meansto produce the signals of a normal signal sequence, which sequence ismade up of groups of various predetermined numbers of signals of saidone type and groups of various predetermined numbers of signals of saidother type, with the type of signals for successive predeterminednumbers of signals alternating until the normal signal sequence iscompleted, means to drive the wipers past the contacts, and a relaywhich can be selectively energized and, when energized, connecting e tThe light circuit or the automobile 'contains and second controlcircuits to further contacts in said banks to modify the control of thecontrol means to produce a modified Signal sequence, which modifiedsignal sequence is made up of said normal signal sequence and anadditional predetermined number of signals of the type opposite the lasttype of the normal signal sequence.

2. In a sending apparatus for remotely controlling the operation of anapparatus from a vehicle, the combination of a signal-generatin means;control means automatically operable upon an initiation of an operationthereof to control the signal-generating means to generate a signalsequence for causing the operation of the remote apparatus; means toinitiate the automatic operation of the control means; further controlmeans to control the signal-generating means to generate a specialsignal sequence for causing the interruption of an operation of theremote apparatus, and means, operable at will after the operation of theremote apparatus has been initiated, for Causing the further controlmeans to be operable to cause the special signal sequence to begenerated whereby an operation of the remote apparatus, once started,can be interrupted at will by signals sent from the sending apparatus inthe vehicle.

3. In a radio transmitting system, the combination of an electronicoscillator; a first control circuit connected to the oscillator andhaving circuit constants for causing the oscillator to produceoscillations at one frequency; a second control circuit for modifyingthe constants of the first control circuit and jointly operabletherewith to cause the oscillator to produce oscillations at a secondfrequency; a control means automatically operable upon an initiation ofan operation thereof to generate a control sequence, said control meansincluding a switch havinga plurality of banks of contacts and wipersengagin corresponding contacts in the several banks during the automaticoperation of the switch, the first control circuit being connected toselected contacts in one of said banks and the second control circuitbeing connected to selected contacts in the other bank of contacts, andthe Wipers rendering the control circuits .efiective when they engagecontacts in the banks to which the control circuits are connected, theswitch causing oscillations to be produced at said one fre-- quencytoiorm one type of signal when the wipers engage contacts to Which saidfirst control circuit is connected and causing oscillations to beproduced at said other frequency to form another type of signal when thewipers engage contacts to which both control circuits have beenconnected, said switch nabling the two control circuits to beselectively eiTective to cause theoscillator to produce a signalsequence containing a plurality of groups of signals with variouspredetermined numbers of signals in the groups and with the signals ofodd-numbered groups being of said one type and with the signals ofeven-numbered groups being of said other type; and means to initiate anoperation of the control means.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,760,479 Colman May 27, 1930 2,069,860 teWart Feb. 9, 19372,118,930 Lilja May 31, 1938 2,505,781 Mallinson May 2, 1950

